VESTIBULAR REFLEX ADAPTATION--PHYSICAL REHABILITATION/SURGICAL INTERVENTIONS

从一个迷宫功能丧失的补偿是一个重要的 临床问题，以及感觉运动适应和 学习。接受急性单侧前庭去传入的患者 (UVD)，作为听神经瘤或Meniere‘s的外科干预 疾病，患有各种前庭、动眼和姿势 精神错乱。最初，他们有剧烈的自发性眼球震颤，这是由于 前庭紧张的突然失衡，在很大程度上会自行解决 几周后。与这种静态不平衡相关的是一个动态的 干扰：前庭的增益(眼速/头部速度)- 眼反射(VOR)对头部旋转的反应显著 减小，向损伤侧旋转时较低。这条线索 姿势稳定、迷失方向、头晕和模糊的问题 头部运动时的视觉。VOR的增益逐渐增加， 变得更加对称。然而，VOR增益的测试具有快速、高精度的特点。 磁头旋转的加速步长显示出减小的和不对称的增益 即使是神经切断术后长达一年。 我们建议进行一系列研究，以加强我们对 对UVD的补偿过程。这些研究将帮助我们更好地 了解正常人的前庭适应，将有助于我们 制定适当的练习，以便最快、最有效地进行 UVD后患者的康复。这个项目有四个主要目标。 第一，研究正常人对不对称前庭刺激的适应性 人类。第二，衡量患者适应这些变化的能力 刺激，并确定在这种情况下适应能力是否增强 它们补偿UVD的能力。第三，设计视觉前庭 提供最快速、最彻底的增益增加的刺激 法线上的VOR，作为将同样的刺激应用于 UVD患者的锻炼。第四，促进前庭功能恢复 函数--即使VOR的增益不能被增强--通过一个 针对视觉目标的快速组合眼球和头部运动的程序。这 TASK再现了UVD患者感到不安的那些情况 在康复过程中；它在临床和实验室的研究可以帮助我们 确定患者采用哪些策略以增强 VOR不足，因此我们可以在 理疗课程。

Compensation from the loss of function of one labyrinth is an important clinical problem, and an excellent example of sensorimotor adaptation and learning. Patients who undergo acute unilateral vestibular deafferentation (UVD), as a surgical intervention for acoustic neuroma or Meniere's disease, suffer from a variety of vestibular, oculomotor, and postural disorders. Initially, they have a vigorous spontaneous nystagmus due to the sudden imbalance of vestibular tone, which largely resolves itself after a few weeks. Associated with this static imbalance is a dynamic disturbance: the gain (eye velocity / head velocity) of the vestibular- ocular reflex (VOR), in response to head rotations, is significantly decreased, and is lower for rotations toward the lesioned side. This leads to problems of postural stability, disorientation, dizziness, and blurred vision during head motion. The gain of the VOR gradually increases and becomes more symmetric. However, tests of VOR gain with rapid, high- acceleration steps of head rotation show a decreased and asymmetric gain even up to a year after nerve section. We propose a series of studies designed to enhance our knowledge of the process of compensation to UVD. These studies will help us better to understand vestibular adaptation in normals, and will aid us in the development of appropriate exercises for the most rapid and effective rehabilitation of patients after UVD. This project has four major aims. First, to study adaptation to asymmetric vestibular stimuli in normal humans. Second, to measure the ability of patients to adapt to these same stimuli, and determine if adaptive capability in this situation enhances their ability to compensate for UVD. Third, to design visual-vestibular stimuli that provide the most rapid and complete increases in the gain of the VOR in normals, as a preliminary to applying these same stimuli to exercises for UVD patients. Fourth, to promote recovery of vestibular function -- even if the gain of the VOR can not be enhanced -- by a program of rapid combined eye and head movements to visual targets. This task reproduces those circumstances that UVD patients find troubling during recovery; its study in the clinic and laboratory can help us to determine those strategies that patients employ in order to augment an insufficient VOR, so that we can specifically target these strategies in programs of physical therapy.